[PATCH v5 07/24] PCI: endpoint: functions: Add an EP function to test PCI

From: Kishon Vijay Abraham I
Date: Mon Mar 27 2017 - 05:47:53 EST


Adds a new endpoint function driver (to program the virtual
test device) making use of the EP-core library.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
drivers/pci/endpoint/Kconfig | 2 +
drivers/pci/endpoint/Makefile | 2 +-
drivers/pci/endpoint/functions/Kconfig | 12 +
drivers/pci/endpoint/functions/Makefile | 5 +
drivers/pci/endpoint/functions/pci-epf-test.c | 510 ++++++++++++++++++++++++++
5 files changed, 530 insertions(+), 1 deletion(-)
create mode 100644 drivers/pci/endpoint/functions/Kconfig
create mode 100644 drivers/pci/endpoint/functions/Makefile
create mode 100644 drivers/pci/endpoint/functions/pci-epf-test.c

diff --git a/drivers/pci/endpoint/Kconfig b/drivers/pci/endpoint/Kconfig
index c86bca9b7de3..c23f146fb5a6 100644
--- a/drivers/pci/endpoint/Kconfig
+++ b/drivers/pci/endpoint/Kconfig
@@ -26,4 +26,6 @@ config PCI_ENDPOINT_CONFIGFS
configure the endpoint function and used to bind the
function with a endpoint controller.

+source "drivers/pci/endpoint/functions/Kconfig"
+
endmenu
diff --git a/drivers/pci/endpoint/Makefile b/drivers/pci/endpoint/Makefile
index 7219d51bb401..1041f80a4645 100644
--- a/drivers/pci/endpoint/Makefile
+++ b/drivers/pci/endpoint/Makefile
@@ -4,4 +4,4 @@

obj-$(CONFIG_PCI_ENDPOINT_CONFIGFS) += pci-ep-cfs.o
obj-$(CONFIG_PCI_ENDPOINT) += pci-epc-core.o pci-epf-core.o\
- pci-epc-mem.o
+ pci-epc-mem.o functions/
diff --git a/drivers/pci/endpoint/functions/Kconfig b/drivers/pci/endpoint/functions/Kconfig
new file mode 100644
index 000000000000..175edad42d2f
--- /dev/null
+++ b/drivers/pci/endpoint/functions/Kconfig
@@ -0,0 +1,12 @@
+#
+# PCI Endpoint Functions
+#
+
+config PCI_EPF_TEST
+ tristate "PCI Endpoint Test driver"
+ depends on PCI_ENDPOINT
+ help
+ Enable this configuration option to enable the test driver
+ for PCI Endpoint.
+
+ If in doubt, say "N" to disable Endpoint test driver.
diff --git a/drivers/pci/endpoint/functions/Makefile b/drivers/pci/endpoint/functions/Makefile
new file mode 100644
index 000000000000..6d94a4801838
--- /dev/null
+++ b/drivers/pci/endpoint/functions/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for PCI Endpoint Functions
+#
+
+obj-$(CONFIG_PCI_EPF_TEST) += pci-epf-test.o
diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c
new file mode 100644
index 000000000000..d6a7a12a99f7
--- /dev/null
+++ b/drivers/pci/endpoint/functions/pci-epf-test.c
@@ -0,0 +1,510 @@
+/**
+ * Test driver to test endpoint functionality
+ *
+ * Copyright (C) 2017 Texas Instruments
+ * Author: Kishon Vijay Abraham I <kishon@xxxxxx>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/pci_ids.h>
+#include <linux/random.h>
+
+#include <linux/pci-epc.h>
+#include <linux/pci-epf.h>
+#include <linux/pci_regs.h>
+
+#define COMMAND_RAISE_LEGACY_IRQ BIT(0)
+#define COMMAND_RAISE_MSI_IRQ BIT(1)
+#define MSI_NUMBER_SHIFT 2
+#define MSI_NUMBER_MASK (0x3f << MSI_NUMBER_SHIFT)
+#define COMMAND_READ BIT(8)
+#define COMMAND_WRITE BIT(9)
+#define COMMAND_COPY BIT(10)
+
+#define STATUS_READ_SUCCESS BIT(0)
+#define STATUS_READ_FAIL BIT(1)
+#define STATUS_WRITE_SUCCESS BIT(2)
+#define STATUS_WRITE_FAIL BIT(3)
+#define STATUS_COPY_SUCCESS BIT(4)
+#define STATUS_COPY_FAIL BIT(5)
+#define STATUS_IRQ_RAISED BIT(6)
+#define STATUS_SRC_ADDR_INVALID BIT(7)
+#define STATUS_DST_ADDR_INVALID BIT(8)
+
+#define TIMER_RESOLUTION 1
+
+static struct workqueue_struct *kpcitest_workqueue;
+
+struct pci_epf_test {
+ void *reg[6];
+ struct pci_epf *epf;
+ struct delayed_work cmd_handler;
+};
+
+struct pci_epf_test_reg {
+ u32 magic;
+ u32 command;
+ u32 status;
+ u64 src_addr;
+ u64 dst_addr;
+ u32 size;
+ u32 checksum;
+} __packed;
+
+static struct pci_epf_header test_header = {
+ .vendorid = PCI_ANY_ID,
+ .deviceid = PCI_ANY_ID,
+ .baseclass_code = PCI_CLASS_OTHERS,
+ .interrupt_pin = PCI_INTERRUPT_INTA,
+};
+
+static int bar_size[] = { 512, 1024, 16384, 131072, 1048576 };
+
+static int pci_epf_test_copy(struct pci_epf_test *epf_test)
+{
+ int ret;
+ void __iomem *src_addr;
+ void __iomem *dst_addr;
+ phys_addr_t src_phys_addr;
+ phys_addr_t dst_phys_addr;
+ struct pci_epf *epf = epf_test->epf;
+ struct device *dev = &epf->dev;
+ struct pci_epc *epc = epf->epc;
+ struct pci_epf_test_reg *reg = epf_test->reg[0];
+
+ src_addr = pci_epc_mem_alloc_addr(epc, &src_phys_addr, reg->size);
+ if (!src_addr) {
+ dev_err(dev, "failed to allocate source address\n");
+ reg->status = STATUS_SRC_ADDR_INVALID;
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = pci_epc_map_addr(epc, src_phys_addr, reg->src_addr, reg->size);
+ if (ret) {
+ dev_err(dev, "failed to map source address\n");
+ reg->status = STATUS_SRC_ADDR_INVALID;
+ goto err_src_addr;
+ }
+
+ dst_addr = pci_epc_mem_alloc_addr(epc, &dst_phys_addr, reg->size);
+ if (!dst_addr) {
+ dev_err(dev, "failed to allocate destination address\n");
+ reg->status = STATUS_DST_ADDR_INVALID;
+ ret = -ENOMEM;
+ goto err_src_map_addr;
+ }
+
+ ret = pci_epc_map_addr(epc, dst_phys_addr, reg->dst_addr, reg->size);
+ if (ret) {
+ dev_err(dev, "failed to map destination address\n");
+ reg->status = STATUS_DST_ADDR_INVALID;
+ goto err_dst_addr;
+ }
+
+ memcpy(dst_addr, src_addr, reg->size);
+
+ pci_epc_unmap_addr(epc, dst_phys_addr);
+
+err_dst_addr:
+ pci_epc_mem_free_addr(epc, dst_phys_addr, dst_addr, reg->size);
+
+err_src_map_addr:
+ pci_epc_unmap_addr(epc, src_phys_addr);
+
+err_src_addr:
+ pci_epc_mem_free_addr(epc, src_phys_addr, src_addr, reg->size);
+
+err:
+ return ret;
+}
+
+static int pci_epf_test_read(struct pci_epf_test *epf_test)
+{
+ int ret;
+ void __iomem *src_addr;
+ void *buf;
+ u32 crc32;
+ phys_addr_t phys_addr;
+ struct pci_epf *epf = epf_test->epf;
+ struct device *dev = &epf->dev;
+ struct pci_epc *epc = epf->epc;
+ struct pci_epf_test_reg *reg = epf_test->reg[0];
+
+ src_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
+ if (!src_addr) {
+ dev_err(dev, "failed to allocate address\n");
+ reg->status = STATUS_SRC_ADDR_INVALID;
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = pci_epc_map_addr(epc, phys_addr, reg->src_addr, reg->size);
+ if (ret) {
+ dev_err(dev, "failed to map address\n");
+ reg->status = STATUS_SRC_ADDR_INVALID;
+ goto err_addr;
+ }
+
+ buf = kzalloc(reg->size, GFP_KERNEL);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto err_map_addr;
+ }
+
+ memcpy(buf, src_addr, reg->size);
+
+ crc32 = crc32_le(~0, buf, reg->size);
+ if (crc32 != reg->checksum)
+ ret = -EIO;
+
+ kfree(buf);
+
+err_map_addr:
+ pci_epc_unmap_addr(epc, phys_addr);
+
+err_addr:
+ pci_epc_mem_free_addr(epc, phys_addr, src_addr, reg->size);
+
+err:
+ return ret;
+}
+
+static int pci_epf_test_write(struct pci_epf_test *epf_test)
+{
+ int ret;
+ void __iomem *dst_addr;
+ void *buf;
+ phys_addr_t phys_addr;
+ struct pci_epf *epf = epf_test->epf;
+ struct device *dev = &epf->dev;
+ struct pci_epc *epc = epf->epc;
+ struct pci_epf_test_reg *reg = epf_test->reg[0];
+
+ dst_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
+ if (!dst_addr) {
+ dev_err(dev, "failed to allocate address\n");
+ reg->status = STATUS_DST_ADDR_INVALID;
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = pci_epc_map_addr(epc, phys_addr, reg->dst_addr, reg->size);
+ if (ret) {
+ dev_err(dev, "failed to map address\n");
+ reg->status = STATUS_DST_ADDR_INVALID;
+ goto err_addr;
+ }
+
+ buf = kzalloc(reg->size, GFP_KERNEL);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto err_map_addr;
+ }
+
+ get_random_bytes(buf, reg->size);
+ reg->checksum = crc32_le(~0, buf, reg->size);
+
+ memcpy(dst_addr, buf, reg->size);
+
+ /*
+ * wait 1ms inorder for the write to complete. Without this delay L3
+ * error in observed in the host system.
+ */
+ mdelay(1);
+
+ kfree(buf);
+
+err_map_addr:
+ pci_epc_unmap_addr(epc, phys_addr);
+
+err_addr:
+ pci_epc_mem_free_addr(epc, phys_addr, dst_addr, reg->size);
+
+err:
+ return ret;
+}
+
+static void pci_epf_test_raise_irq(struct pci_epf_test *epf_test)
+{
+ u8 irq;
+ u8 msi_count;
+ struct pci_epf *epf = epf_test->epf;
+ struct pci_epc *epc = epf->epc;
+ struct pci_epf_test_reg *reg = epf_test->reg[0];
+
+ reg->status |= STATUS_IRQ_RAISED;
+ msi_count = pci_epc_get_msi(epc);
+ irq = (reg->command & MSI_NUMBER_MASK) >> MSI_NUMBER_SHIFT;
+ if (irq > msi_count || msi_count <= 0)
+ pci_epc_raise_irq(epc, PCI_EPC_IRQ_LEGACY, 0);
+ else
+ pci_epc_raise_irq(epc, PCI_EPC_IRQ_MSI, irq);
+}
+
+static void pci_epf_test_cmd_handler(struct work_struct *work)
+{
+ int ret;
+ u8 irq;
+ u8 msi_count;
+ struct pci_epf_test *epf_test = container_of(work, struct pci_epf_test,
+ cmd_handler.work);
+ struct pci_epf *epf = epf_test->epf;
+ struct pci_epc *epc = epf->epc;
+ struct pci_epf_test_reg *reg = epf_test->reg[0];
+
+ if (!reg->command)
+ goto reset_handler;
+
+ if (reg->command & COMMAND_RAISE_LEGACY_IRQ) {
+ reg->status = STATUS_IRQ_RAISED;
+ pci_epc_raise_irq(epc, PCI_EPC_IRQ_LEGACY, 0);
+ goto reset_handler;
+ }
+
+ if (reg->command & COMMAND_WRITE) {
+ ret = pci_epf_test_write(epf_test);
+ if (ret)
+ reg->status |= STATUS_WRITE_FAIL;
+ else
+ reg->status |= STATUS_WRITE_SUCCESS;
+ pci_epf_test_raise_irq(epf_test);
+ goto reset_handler;
+ }
+
+ if (reg->command & COMMAND_READ) {
+ ret = pci_epf_test_read(epf_test);
+ if (!ret)
+ reg->status |= STATUS_READ_SUCCESS;
+ else
+ reg->status |= STATUS_READ_FAIL;
+ pci_epf_test_raise_irq(epf_test);
+ goto reset_handler;
+ }
+
+ if (reg->command & COMMAND_COPY) {
+ ret = pci_epf_test_copy(epf_test);
+ if (!ret)
+ reg->status |= STATUS_COPY_SUCCESS;
+ else
+ reg->status |= STATUS_COPY_FAIL;
+ pci_epf_test_raise_irq(epf_test);
+ goto reset_handler;
+ }
+
+ if (reg->command & COMMAND_RAISE_MSI_IRQ) {
+ msi_count = pci_epc_get_msi(epc);
+ irq = (reg->command & MSI_NUMBER_MASK) >> MSI_NUMBER_SHIFT;
+ if (irq > msi_count || msi_count <= 0)
+ goto reset_handler;
+ reg->status = STATUS_IRQ_RAISED;
+ pci_epc_raise_irq(epc, PCI_EPC_IRQ_MSI, irq);
+ goto reset_handler;
+ }
+
+reset_handler:
+ reg->command = 0;
+
+ queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
+ msecs_to_jiffies(1));
+}
+
+static void pci_epf_test_linkup(struct pci_epf *epf)
+{
+ struct pci_epf_test *epf_test = epf_get_drvdata(epf);
+
+ queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
+ msecs_to_jiffies(1));
+}
+
+static void pci_epf_test_unbind(struct pci_epf *epf)
+{
+ struct pci_epf_test *epf_test = epf_get_drvdata(epf);
+ struct pci_epc *epc = epf->epc;
+ int bar;
+
+ cancel_delayed_work(&epf_test->cmd_handler);
+ pci_epc_stop(epc);
+ for (bar = BAR_0; bar <= BAR_5; bar++) {
+ if (epf_test->reg[bar]) {
+ pci_epf_free_space(epf, epf_test->reg[bar], bar);
+ pci_epc_clear_bar(epc, bar);
+ }
+ }
+}
+
+static int pci_epf_test_set_bar(struct pci_epf *epf)
+{
+ int flags;
+ int bar;
+ int ret;
+ struct pci_epf_bar *epf_bar;
+ struct pci_epc *epc = epf->epc;
+ struct device *dev = &epf->dev;
+ struct pci_epf_test *epf_test = epf_get_drvdata(epf);
+
+ flags = PCI_BASE_ADDRESS_SPACE_MEMORY | PCI_BASE_ADDRESS_MEM_TYPE_32;
+ if (sizeof(dma_addr_t) == 0x8)
+ flags |= PCI_BASE_ADDRESS_MEM_TYPE_64;
+
+ for (bar = BAR_0; bar <= BAR_5; bar++) {
+ epf_bar = &epf->bar[bar];
+ ret = pci_epc_set_bar(epc, bar, epf_bar->phys_addr,
+ epf_bar->size, flags);
+ if (ret) {
+ pci_epf_free_space(epf, epf_test->reg[bar], bar);
+ dev_err(dev, "failed to set BAR%d\n", bar);
+ if (bar == BAR_0)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int pci_epf_test_alloc_space(struct pci_epf *epf)
+{
+ struct pci_epf_test *epf_test = epf_get_drvdata(epf);
+ struct device *dev = &epf->dev;
+ void *base;
+ int bar;
+
+ base = pci_epf_alloc_space(epf, sizeof(struct pci_epf_test_reg),
+ BAR_0);
+ if (!base) {
+ dev_err(dev, "failed to allocated register space\n");
+ return -ENOMEM;
+ }
+ epf_test->reg[0] = base;
+
+ for (bar = BAR_1; bar <= BAR_5; bar++) {
+ base = pci_epf_alloc_space(epf, bar_size[bar - 1], bar);
+ if (!base)
+ dev_err(dev, "failed to allocate space for BAR%d\n",
+ bar);
+ epf_test->reg[bar] = base;
+ }
+
+ return 0;
+}
+
+static int pci_epf_test_bind(struct pci_epf *epf)
+{
+ int ret;
+ struct pci_epf_header *header = epf->header;
+ struct pci_epc *epc = epf->epc;
+ struct device *dev = &epf->dev;
+
+ if (WARN_ON_ONCE(!epc))
+ return -EINVAL;
+
+ ret = pci_epc_write_header(epc, header);
+ if (ret) {
+ dev_err(dev, "configuration header write failed\n");
+ return ret;
+ }
+
+ ret = pci_epf_test_alloc_space(epf);
+ if (ret)
+ return ret;
+
+ ret = pci_epf_test_set_bar(epf);
+ if (ret)
+ return ret;
+
+ ret = pci_epc_set_msi(epc, epf->msi_interrupts);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int pci_epf_test_probe(struct pci_epf *epf)
+{
+ struct pci_epf_test *epf_test;
+ struct device *dev = &epf->dev;
+
+ epf_test = devm_kzalloc(dev, sizeof(*epf_test), GFP_KERNEL);
+ if (!epf)
+ return -ENOMEM;
+
+ epf->header = &test_header;
+ epf_test->epf = epf;
+
+ INIT_DELAYED_WORK(&epf_test->cmd_handler, pci_epf_test_cmd_handler);
+
+ epf_set_drvdata(epf, epf_test);
+ return 0;
+}
+
+static int pci_epf_test_remove(struct pci_epf *epf)
+{
+ struct pci_epf_test *epf_test = epf_get_drvdata(epf);
+
+ kfree(epf_test);
+ return 0;
+}
+
+static struct pci_epf_ops ops = {
+ .unbind = pci_epf_test_unbind,
+ .bind = pci_epf_test_bind,
+ .linkup = pci_epf_test_linkup,
+};
+
+static const struct pci_epf_device_id pci_epf_test_ids[] = {
+ {
+ .name = "pci_epf_test",
+ },
+ {},
+};
+
+static struct pci_epf_driver test_driver = {
+ .driver.name = "pci_epf_test",
+ .probe = pci_epf_test_probe,
+ .remove = pci_epf_test_remove,
+ .id_table = pci_epf_test_ids,
+ .ops = &ops,
+ .owner = THIS_MODULE,
+};
+
+static int __init pci_epf_test_init(void)
+{
+ int ret;
+
+ kpcitest_workqueue = alloc_workqueue("kpcitest",
+ WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
+ ret = pci_epf_register_driver(&test_driver);
+ if (ret) {
+ pr_err("failed to register pci epf test driver --> %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+module_init(pci_epf_test_init);
+
+static void __exit pci_epf_test_exit(void)
+{
+ pci_epf_unregister_driver(&test_driver);
+}
+module_exit(pci_epf_test_exit);
+
+MODULE_DESCRIPTION("PCI EPF TEST DRIVER");
+MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@xxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.11.0